================================================================= Logtalk - Object oriented extension to Prolog Release 2.29.1 Copyright (c) 1998-2006 Paulo Moura. All Rights Reserved. ================================================================= To load this example and for sample queries, please see the SCRIPT file. This example shows the use of meta-predicates in Logtalk. Meta-predicates are predicates whose head contains arguments that will be called as goals in the body of the predicate definition. This example defines two objects: sort(_) this is a parametric object containing a method that implements the quicksort sorting algorithm; the parameter is interpreted as the type of the elements being sorted tracer this object implements a meta-predicate that is used by sort(_) to trace the sorting algorithm steps